Pulverizer



Jan. 15, 1924. 1,480,767

O. A. KREUTZEERG PULVERIZER Filed Feb. 24. 1920 6 sheets-Sheet 1v www"Jan, 15 1924.

O. A. KREUTZBERG PULVERI ZER kFiled Feb. 24, 1920 6 Sheets-Sheet 2@hw/66: ffy?,

4 1,480,767 o. A. KREUTZBERG PULVERIZER l Filed Feb. 24. 1920 6sheets-sheet z w ma M j www m r I ...,...u .a W@ ,Alla a 10, w, ,n

Jan. 15 1924.

O. A. KREUTZBERG PULVERIZER Jan. 15 l1924. 11,480,761

Filed Feb. 24, 1920 6-Shee`tS-Sheeb 4 fzg m ym v Jan. 15 1924.

. A. KREUTZBERG PULVERIZER Filed Feb. 24, 1920 6 sheets-sheet 5vWITNESS.

Jan. 15 1924. 1,480,767

o. A. KREUTZBERG PULVERI ZER Filed Feb. 24, 1920 6 SheeliS-SheebWITNEISSJ [1V VENTOR f//s A TTORNE Y6:

Patented Jan. 15, 1924.

UNITED STATES OTTO A. KREUTZBERG, F LAKE BLUFF, TLLINOIS.

PULVEBIZER.

Application filed February 24, 1920.

To aZZ'wLo/m it may concer/a.'

Be it lmown that I, O'r'ro A. Kimura BERG, a citizen of the UnitedStates, residing at Lake Bluff, in the county of Lake and State ofIllinois, have invented certain new and useful Improve-ments inPulverizers, of which the following is a specification, reference beinghad to the accompanying drawings, forming a part thereof.

The purpose of this invention is to pro vide an improved constructionfor pulverizing hard material, adapted in one of its forms forseparating the material according to fmeness, so that only that which ispulverized to a desired degree shall be dejlivered, the remainder beingreturned for further treatment. ItV consists in the elements andfeatures of construction shown and described, as indicated in theclaims.

In the drawings Figure 1 is a vertical axial section of a structureembodying this invention.

Figure 2 is a top plan view with the casing partly broken away to showthe interior construct-ion.

Figure 3 is a section at the same plane as Figure l showing a. partitionsubstituted for a deflector shown in Figure l, to adapt the device `to amodified form of operation.

Figure 4: is a plan view of the rollers, showing a modified form.

Figure 5 is a section at the line, 5--5, on Figure fl. j

Figure 6 is a section at the line, 66, on Figure `4.

Figure 7 is a View similar to Figure l showing a modification. j

Figure 8 is a similar view showing another modification.

The structure shown in the drawings comprises a support, l, upon whichthere is mounted for rotation about a vertical axis, a table, 21, havingits upper face dished for lodgment thereon of rolls, 3, which aremounted for rotation upon axles, 4t, hinged upon brackets, 5, mountedupon the supports, the hinge position and the form of the rolls beingadapted to the slope of the dished tableV so that the rolls lodge alongtheir entire length upon the latter and rotated about their own ailes bythe rotation of the table about its axis. rlihe material to be treatedis designed to be delivered through a conduit, 6, which delivers it atthe center of the table over an upraised central portion, 7, thereof, bywhich serial No. 360,820.

it is initially spread outwardly, the upraise being sloping, so as tolodge upon the table at a little distance from the center, whereliy `thecentrifugal tendency resulting from the rotation of the table operatesto move it further outward and enter it between and under the rolls asthey roll upon the table. The centrifugal action of the materialretarded by gravity due to the upward, outward slope of the dishedtable, causes the material -to advance outwardly along the table ontothe rolls, slowly, following in fact a spiral path, and being repeatedly`crushed and ground 'by the rolls until it emerges at the circumferenceof the table, ground or pulverized to the desired. degree of iineness.The rate of its advance outward from the center` `of the table to thecircumference, and thereby the duration of its exposure to thepulverizing action of the rolls on the table, is regulated by the speedof rotation of the table, said speed being adapted to the character ofthe material, so that it will be kept within the operation of the devicelong enough according to experience. to reduce the most refractory partsto the desired degree of fineness by the time lit is advanced to thecircumference of the table. The support, l, is apen tured at an annulararea situated under the outer circumference of table, as seen at. l, sothat the material delivered over the circumference passes through saidapertures la; and from the `lower side of the support there is suspendeda funnel or gathering casing, lli, encompassing the annular aperturedareaw of the support, so that the inaterial delivered through saidapertures is received by said casing and gathered for discharge at itsdischarge mouth, 1.4i.

The means for rotating the table consists of a gear, 7. mounted upon thestem or spindle, 2, of the table, which is driven by a pinion 8, mountedon a driving shaft, 9. The shaft and gears are enclosed in a heus ing,l0, which is suspended from the lower side of the support, l, and whichcarries at the lower end a. step bearing, a, for the spindle or shaft,2a', of the table, and in addition an adjustable step bearing or end.

stop, 10b,` for the end of said spindle. The

fitting containing the journal bearing, 10., carries also a journalbearing, 10d, for the inner end of the shaft, 9, of the driving pinion,8. The gear enclosing and greaseu retaining chamber of this housing isclosed at the top by a sheet metal partitioning diaphragm, ll, and abovethe level of that diaphragm the housing is laterally aper* tured as seenat 10, for a purpose hereinafter explained. The gear and greasehousing,A it will be seen, enclosing the gears, protects them againstdust from the pulverized material, and also prevents the grease fromescaping to mingle with that material as the latter is delivered throughthe funnel casing, lll. Suitable provision is made vby removableclosures, 10 and lllf, for obtaining access to the gears, or forsupplying grease to the housing.

A very desirable mode of use of this structure consists in causing acurrent of air to pass through it from below the table up aroundthecircumference thereof, thereby traversing the film of materialdelivered over the circumference of the table, such air current beinggraduated as to its velocity so as to pick up the material thusdelivered and carry it up above the rolls, where those portions whicharev too coarse to be held suspended by the air current of the velocityselected, will be dropped and fall again between the rolls onto thetable for further crushing and grinding, while the liner portions whichcan be lifted by the current of a given velocity, are carried out by theair current. F or this purpose there is provided a casing, 12, enclosingthe table and the rolls above the support. said casing being completelyclosed except where the removable sectors, 12X, hereinafter mentioned,are apertured for the axles of the rolls, which substantially occupy andclose said apertures; and a discharge conduit, 13, leads from the top ofsaid casing for delivery of the material lifted by the air current intoa storage bin (not shown) at any desire(` distance away. For the purposeof admitting and directing the air current, the. support, l, isapertured at an annular area intermediate the bearing of the spindle,2", and the annular area at which the housing, l0, is secured, theapertures at said annular area being seen at 1. These apertures, it willbe seen lead into a space in the upper part of the housing, l0, of whichthe enclosing Wall is apertured at 10C, as above described,

l/Vhen the device is to be used with an air current for separation asdescribed, there is preferably inserted a frusto-conical sheet metal airdeflector, l5. to direct the current of air moving radially outwardunder the table and turning upward at the outer margin of the table topass across the current of discharged material above described, thuspreventing eddies and loss of velocity of the air current in making thischange of direction. Also for the purpose of deflecting the air currentcarrying the lifted material from the directly-upward course inwardlytoward the discharge pipe lil` and to cause the heavy materia when itfalls lo fall upon the table` between the rollsy or upon the rolls.there is preferably provided a truste-conical sheet metal delleetorVlli. projecting inwardly from the easing. lf2. al a level slightly abovethe 1evel ol' the outer circumference of the table. 2.

When the structure deseriheil is einployed without the air ciurent. soIlat the pulverized material is delivered downwardly from the outercircuinfereiu'e of the rotating table through the apertures, l, into thefunnel casing, 14, there may he desir ably inserted a sheet nieta ring.l?. resting 0n the support. l, just inside the annular area of theapertures, in. and extemling up nearly into contact with the lower sideof the rotating table. to prevent the pulverized material from passinginwardly under the table, whereby it would become lodged upon the top.ll. of the gear and gres chamber.

When this structure is employed with the air current for separating theliner troni the coarser material, the gradation of the material,that is,the pointl oit separation as to fineness between that which ie liftedand carried out and that which is not lifted but returned for furtherpulverizing-it `will be understood is determined by 'the ,'eloeity oEthe air current. and therefore the air cui rent is designed to beproduced by emausl fans, and the like, not shown. and which may besituated in any convenient point in the conduit leading' from thecasing, i2. Some assistance in respect to the movement of the aircurrent may be obtained by providing the rotating table. on its lowerside with fan blades,` 1X, for which a chamber 'is formed by theuiujlerlying siipport. l. und the frusto-conical deflector abovedescribed. such fan case having intake around thiI eeuter through theapertures. l". and its discharge at the peripheral gap between the outercircumference of the table. l. and the upper margin of the del-lector.l5. These fan blades are preferably made removable, being secured bybolts. Q", as shown. and they are preferably removed when operaiingwithout air current for separation or grading of the material.

The casing, 1Q, has apertures mesnil by removable sectors, 12X. topermit the rolls. Il. lo be 'swung out of the casing' for any atlentionwhich may be required frein time lo time.

Preferably the table. 2. and the rolls, I5. have their operatingsurfaces provided with detachable wear plates or sectors. lo the case ofthe table the wear plate is made iu sectors, 2", as shown; and in the eof the rolls it may be a single piece shell, 3*.

Upon considering the operation of the rotating table and rolls ridingthereon and revolved thereby for crushing and grinding llo inserermaterial passed between them, it will be seen that the circumferentialspeed of the table increasing from center outward proportionately to theradius, will not vary at the same rate as the circumferential speed ofthe rolls riding` thereon; and that therefore the roll deriving itscircinnferential speed from some point of its Contact with the table atwhich the frictional engagement happens to be greatest by reason of thecharacter of the material engaged between the surfaces will have therubbing action over the table at all other points of its length; and itmay be judged that in all probal'iility the rnbbing action will begreatest in the aggregate,that is, throughout any continued time ofoperation, toward the outer end of the roll. On this account and toavoid. 'the tendency to unequal wear at dili'erent points in the lengthof the roll, or to reduce the ineopiality` to a minimum, it may be founddesirable to subdivide each of the rolls into two or more sections,lying side by side along` the axis of the roll, and each revolvingindependentlyY upon the axle. flush con struction is shown in Figures41:, 5 and 6, in which two of the tour rolls are divided into threesections, 31, 3 and 3", and the other two are divided into two sections,fp and 31'. The purpose of dividing the different rolls into a differentnumber of sectors, is to prevent too definite Zoning of the material onthe table by the different action which the seetioi'is of the subdividedrolls may cause, the ytones or paths of travel of the two-sections ofthe rolls which are thus divided laminar the paths of the. threesections of the other rolls which are so divided.

ln Figure 7 there is shown a modification comprising means forregulating the velocity oit the air current through the casing at apoint in its path at which material which may be dropped from the aircurrent by reason of reduced velocity may fall on the table forrepeating the pulverixing operation. 'l`he means shown consists of anadjustable discharge sleeve, 20., which as shown comprises twotelescoping members, telescopic-,ally niounted in the discharge pipe,13, and adapted to protrude below that pipe in the chamber enclosed bythe casing, 1&2, above the table and roll. rllhe lower member et thetclescoiiing sleeve has its lower end provided with a flaring or funnelinouthpieee.,l 30e, whose diameter approxi mates that of the table, sothat it substantially overhangs the rolls. ll.. windlass shaft, mount-edin the discharge pipe, 13, is connected by' acable, 22, wound upon itwith the inner member of the telescoping sleeve, Q0, :for raising it andpermitting it to descend. or be extended down into the casing lchamber,` any suitable means not shown, beii provided for locking thewindlass to uphold the sleeve. l/lhen the telescoping sleeve is loweredso that the funnel mouth is positioned at a relatively short distanceabove the rolls and at dotted line position shown in Figure 7, theshortness of the path for the air from the annular inlet at l to saidfunnel mouth causes the air current to be confined pretty closely withindirect lines from the outer margin of the annular area, l, and thecircumferenceof the intake of the sleeve, the air path ex pandingsomewhatas indicated in dotted lines, 0J, on Figure i", thecross-section of said air path being` maximum, and the velocity minimum,at a plane somewhat below said intake.v for example, as will be notedbythe dotted line, wiii-fill, on. Figure 'i'. llllhen the `telescopingsleeve is drawn up so as to position the funnel .mouth at a higherlevel.. as

at the position shown in full line on Figure 7, the air path tends toexpand somewhat, as indicated by the dotted line, Z, on .lifigure 7; andthe maximum cross-section of said path will be found at some such pointas indicated by the dotted lines, m, an, on Figure 7. llhe maximumcross-section of the air path, it will be readily understood, increasesas the discharge sleeve is withdrawn upward from the table; and theminimum velocity which exists at the maximum crossscction, thereforelower as the adjustment of the sleeve is higher.

'lhe lower the velocity of the air current at the point of minimumvelocity, the liner the material must be to be carried up and out of thecasing by the air` current, all coarser material being dropped bacl;onto the table for regrinding. lt will be seen, therefore, that by'aising and lowering the sleeve, 20. the operator may control the de-`gree of .fineness to which the material must be reduced before it willbe carried out by the air current.

.et further modiiication is shown in l? ure 8 in which the constructionis the same as that shown in Figure 7, except that the upper partv ofthe casing shown at 25 is cylindrical and the funnel mouth-piece, 20,lits slidingly within this cylindrical casing, operating piston-wisetherein as the sleeve is raised and lowered; and there is mounted abovethe center of the table a return-pipe carried by straps, 27, extendingolf to 'the casing, said return pipe being aligned with the sleeve, 20,so that there is formed be tween the upper end of the retin-n pipe andthe lower end of the sleeve, (disregarding the funnel mouth-piece of thelatter), what may be regarded as a gateway in the air path, whosecapacity for the passage of the air current is the circumferential areaof a cone frustum whose diameters are those diameters of the proximateends of the return pipe,` 26, and sleeve, 20, and whose length is theaxial distance between said proximate ends. This area becomes theremlll() fore the cross-section of the air path at its maximum point, andtherefore the point of minimum velocity, and the point at which materialis too coarse to be carried up by the air current at said minimumvelocity will be dropped into the return pipe and 'with said adjustment.

thereby returned to the table for re-grinding. It will be seen that thevertical adjustment of the sleeve in this construction varies definitelyand exactly proportionatelyY The area of this gate-way lor cross-sectionof the air path thereby grades the material as in the construction shownin Figure 7 Whether the gradation is more accurate or exact than in theconstruction shown in Figure 7 or not, it at least has the advantage ofbeing more definitely calculable.

For facilitating the initial engagement and entrance of the materialunder the conical rollers 3, said rollers are preferably peripherallynotched as shown at 3a, about the smaller end, said notches being ofcourse in the removable wearing rings or shells of said rollers, asshown on the shells 3X in Fig. l, and on the inner-end rings 3P and 3 asshown in Figures 3, 5 and 6.

I claim 1. A pulverizer comprising in combination with a fixed support,a rotating table Whose upper surface comprises a central upraisedportion and an annular track encompassing said portion, said annularsurface being inclined slightly upward substantially from the centralup-raised portion to the outer edge of the table; pulverizing rollerslodged to roll upon the annular inclined surface and having their shaftspivoted to permit vertical oscillation of the rollers in planessubstantially radial with respect to the table, whereby nearly theentire weight of the rollers operates for crushing material on thetable; means for delivering the material to be treated onto the tableadjacent the inner ends of the rollers, and means for receiving thepulverized material from the outer circumference of the table.

2. In the construction defined in claim 1, foregoing, the rollers beingfrusto-conical with the greater diameter at the outer end.

3. A pulverizer comprising in combination With a fixed support, arotating table whose upper surface comprises a central upraised portionand an annular portion encompassing the same which is inclined slightlyupward substantially from the central rip-raised portion to the outeredge of the table forming an annular track; pulverizing rollers andaxles on which they are respectively journaled free for rotation byfrictional engagement with the annular inclined track, whereby nearlythe entire weight of the rollers operates for'erushing material on thetable; means for delivering the material to be treated at the inner endsof the rollers, and means for receiving the pulverized material from thecircumference of the table.

4. In the construction defined in claim 3, foregoing, one or more of therollers being composed of a plurality of side-by-side members mounted onthe axle for independent rotation thereabout.

5. In the construction defined in claim 3, foregoing. certain of therollers being composed of a plurality of side-by-side. members mountedon the axle for independent rotation thereabout, said severalplural-membered rollers having their corresponding members of differentlengths, so that the track on the table of one of the saidpluralmembered rolls laps on the track of adjacent members of another ofsaid plural-membered rolls.

6. In combination a pulverizing apparatus comprising a support adaptedto receive the material to be pulverized at a central area of saidsupport to deliver it at an outer circumferential area thereof, meansfor producing an upwardly moving air current at said circumferentialarea, the support comprising a web extending under the pulverizing meanshaving an air inlet aperture positioned with respect to the pulverizingmeans to form an open air path from said inlet aperture to saidcircumferential area.

7. In the construction defined in claim 6, foregoing, the pulverizingmeans comprising a rotating table and rollers there-above co-operatingtherewith for reducing the material introduced between the table and therollers, the table having fan blades projecting from its under side, thecasing and support together comprising parts which form a fan chamber inwhich said blades revolve, said chamber extending to saidcircumferential area for air discharge thereat.

8. A pulverizer comprising in combination with a fixed support, a tablemounted for rotation and means for rotating it; means above the tableco-operating therewith for pulverizing the material delivered onto thetable; a casing enclosing the table and the pulverizing means; thesupport comprising a web extending underneath the table and aperturedthereunder for admission of air to the casing, the means for rotatingthe table comprising a vertical shaft `iournaled in the support; a gearhousing suspended from the support having a lubricant and gear chambercompletely closed at the upper side, and having apertures above saidupper side closure for admission of air through the suspending means tothe under side of the table.

9. A pulverizer comprising in combination with fixed supporting means, arotating table and means co-operating therewith for pulverizing materialdelivered thereonto, the table being adapted for delivery of said lua i,cadrer material therefrom centritugally at an outer delivery zone aboutthe margin of the table; means for producing an upward air currentthrough said delivery zone, the table support being apertured at acorresponding downward delivery zone under said upward delivery zone fordelivery by gravity of material which the upward air current i'ails tolift, and a casingP element depending from the support encompassing;said downward delivery zone and converging to a discharge mouth.

10. In combination with a pulverizing apparatus which comprises arelatively rotating table adapted to receive the material to he treatedat zone proximate to the center of the table; roller system thereabovefor pulverizing material delivered thereto; means for producing` anupward air current around the inargin of the table; a casing enclosingthe table and roller system and extending up `for a considerabledistance thereabove and having air discharge at the top; a sleevevertically adjustable in the air discharge connection and constitutingthe air discharge passa-ege from the casing, and a return pipe i'ordelivering back to the table material dropped from the air current, saidreturn pipe being` iixedly positioned substantially in axial alignmentwith the adjustable sleeve, with the discharge mouth above the receivingzone of the table; whereby the vertical distance between the lower endof the adjustable sleeve and the upper end ot the return pipe is thevariable dimenw sion o'l the path oi' the air current at the point oflow velocity` and determines the grading of the material lifted by thecurrent.

n testimony whereof, il have hereunto set my hand at Chicago, illinois,this 12th day ot February, 1920.

@TTU A. KREUTZBERG.

